1. Field of the Invention
This invention relates generally to sheet feeding or delivering and more particularly to feeding pack advancers; specifically, the invention relates to apparatus for feeding blanks of corrugated paperboard and the like from the bottom of a stack in shingled fashion for transport to a blank receiving station such as the feed hopper of a printing press.
2. Description of the Prior Art
It has long been a goal of the corrugating industry to achieve optimum feeding of corrugated blanks to printing presses and the like. The known apparatuses for automatic feeding of corrugated paperboard have not been satisfactory in that they have lacked the ability to consistently feed a wide range of sizes and shapes of corrugated board to the typical printing presses. The present invention provides an apparatus for feeding corrugated paperboard which overcomes the disadvantages found in the known corrugated board feeding apparatus, and which provides the desired consistency in feeding wide ranges of sizes and shapes of paperboard to, for example, the feed hopper of a printing press.
Sheet feeders per se are used for many applications such as feeding small punched computer cards to newspapers to very large sheets or blanks of corrugated or solid fibre paperboard to sheets of wood and the like. Many feeders are adapted to feed single sheets one at a time in serial fashion, either in timed or untimed relation to portions of associated equipment; still others are adapted to feed sheets in overlapped or shingled fashion. The feeding portion of the present invention falls into the latter category.
Examples of feeders for feeding shingled sheets may be found by referring to U.S. Pat. Nos. 3,262,697, 3,776,554, 3,622,149, and 3,522,943, to name but a few. However, the primary purpose of the present invention is to feed blanks of corrugated paperboard from a stack of such blanks and transport them to the feed hopper of a blank printing press or similar machine to achieve automatic loading of the press as opposed to the customary manual loading. Such press loaders, as they are commonly called, currently exist and are of many different types. Pertinent examples may be found in U.S. Pat. Nos. 3,422,969, 3,643,939, 3,815,762, and 3,827,576 to generally show the state of the art.
Press loading machines of the type mentioned above are usually quite large, complex, and expensive. In addition, many are limited to loading a fairly small range of blank sizes and some suffer from a lack of reliability which defeats the purpose for which they are intended.
Accordingly, the principal object of the present invention is to provide a press loading machine of relatively simple construction capable of loading a wide range of blank sizes and characterized by the desired reliability of operation.
Another primary object of the present invention is to provide apparatus for feeding corrugated blank material and the like from a stack of blanks to a receiving station, wherein the blanks are removed from the bottom of the stack and transferred in shingled relation.
Another object of the present invention is to provide an apparatus for feeding corrugated blank material and the like from a stack of blanks in shingled form along a predetermined path to a receiving station such as the feed hopper of a printing press, the apparatus employing spanking means adjacent the feed hopper to maintain proper orientation of the blanks as they are fed into the feed hopper.
Another object of the present invention is to provide apparatus for feeding corrugated blanks and the like as described which includes a novel control gate operative to effect selective shingling of blanks fed from the bottom of a stack of blanks by a belt-over-roller conveyor.